Add the PPC fcpsgn instruction

Modern PPC cores support a floating-point copysign instruction, and we can use
this to lower the FCOPYSIGN node (which is created from calls to the libm
copysign function). A couple of extra patterns are necessary because the
operand types of FCOPYSIGN need not agree.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188653 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 2b83a22..bc55d38 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -149,8 +149,13 @@
         Subtarget->hasFRSQRTES() && Subtarget->hasFRES()))
     setOperationAction(ISD::FSQRT, MVT::f32, Expand);
 
-  setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
-  setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
+  if (Subtarget->hasFCPSGN()) {
+    setOperationAction(ISD::FCOPYSIGN, MVT::f64, Legal);
+    setOperationAction(ISD::FCOPYSIGN, MVT::f32, Legal);
+  } else {
+    setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
+    setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
+  }
 
   if (Subtarget->hasFPRND()) {
     setOperationAction(ISD::FFLOOR, MVT::f64, Legal);